JP4946203B2 - Electro-optical device and electronic apparatus including the same - Google Patents

Description

  The present invention relates to a technical field of an electro-optical device such as a liquid crystal device, and an electronic apparatus such as a liquid crystal projector including the electro-optical device.

  This type of electro-optical device includes, on a substrate, a pixel electrode, a scanning line for selectively driving the pixel electrode, a data line, and a TFT (Thin Film Transistor) as a pixel switching element. The active matrix driving is possible. In addition, a storage capacitor may be provided between the TFT and the pixel electrode for the purpose of increasing the contrast.

  Here, the active matrix drive controls the operation of the TFT by supplying a scanning signal to the scanning line, and is turned on by the scanning signal by supplying an image signal to the data line. In the driving method, an electric field corresponding to the image signal is applied to the pixel electrode corresponding to the TFT. As a method of supplying the image signal, for example, a method of sequentially supplying an image signal to each of the data lines, or a number of data lines adjacent to each other by serial-parallel conversion of the image signal, There is a method of supplying image signals simultaneously for each group.

  The electro-optical device driven in this way has a technical problem that display unevenness occurs due to push-down of the image signal potential written to the data line. That is, the case where the method of supplying the image signal simultaneously for each of the groups exemplified above will be described as an example. In this case, at the boundary between two adjacent groups, the image is substantially aligned with the data line. There is a problem that uneven display appears. In Patent Document 1, the applicant of the present application discloses a technique of providing a capacitor on a data line as means for solving such a technical problem.

Japanese Patent Laid-Open No. 2004-125887

  On the other hand, such an electro-optical device has a general demand for higher density and smaller size of the device. According to the technique disclosed in Patent Document 1, the occurrence of display unevenness is reduced by providing a capacitor on the data line. However, by providing such a capacitor, the density and size of the device can be increased. There is a technical problem that it may be difficult to do.

  The present invention has been made in view of, for example, the above-described problems, and is an electro-optical device capable of displaying a high-quality image without display unevenness along a data line while realizing high density and downsizing of the device. It is an object to provide a device and an electronic apparatus including the electro-optical device.

In order to solve the above problems, a first electro-optical device according to the present invention is provided in a pixel region corresponding to a plurality of data lines and a plurality of scanning lines intersecting with each other and the intersection of the data lines and the scanning lines. and pixel electrodes which are said being electrically connected to the pixel electrode, the lower electrode, the lower electrode is different from the upper electrodes provided on the layer, and between the upper electrode and the lower electrode A storage capacitor having a provided dielectric film; an additional capacitor electrically connected to the data line and having the same stacked structure as the storage capacitor outside the pixel region; and the plurality of data lines N image signals for supplying N systems of serial-parallel converted image signals for a plurality of data line groups each including N data lines (where N is a natural number of 3 or more). Of the additional capacity, A capacitance value of a first additional capacitor electrically connected to a data line located at the end of the group of N data lines, and a data line located at the end of the group among the N data lines; The capacitance values of the second additional capacitors electrically connected to different data lines are different from each other .

  According to the first electro-optical device of the present invention, during the operation, the switching operation of the pixel switching element such as a thin film transistor is controlled through the scanning line, and the image signal is supplied through the data line. A voltage corresponding to the image signal is applied to the pixel electrode via the pixel switching element.

  In the present invention, the potential holding characteristic of the pixel electrode can be enhanced by the storage capacitor connected to the pixel electrode and the pixel switching element. One of the lower electrode and the upper electrode constituting the storage capacitor is electrically connected to the pixel electrode and the pixel switching element, functions as a pixel potential side capacitor electrode, and constitutes the storage capacitor. The other is electrically connected to, for example, a fixed potential line having a predetermined potential, and functions as a fixed potential side capacitor electrode.

  Furthermore, the present invention includes an additional capacitor electrically connected to the data line. Therefore, for example, by adding the additional capacitance to the wiring capacitance of the data line or the capacitance generated by the overlapping of the data line and another wiring, the capacitance around the data line can be appropriately ensured. Therefore, it is possible to suppress a change in the potential that the data line should hold, that is, a push-down of the image signal potential written to the data line. As a result, it is possible to reduce or prevent the occurrence of display unevenness along, for example, the data line due to the push-down of the image signal potential written to the data line.

  Particularly in the present invention, the additional capacitor has the same stacked structure as the storage capacitor. Here, “the same laminated structure” means that the order of lamination of the layers is the same. That is, the additional capacitor is sandwiched between one electrode formed from the same film as the lower electrode of the storage capacitor, another electrode formed from the same film as the upper electrode of the storage capacitor, and the pair of electrodes. And a dielectric film. Here, “formed from the same film” means that a precursor film common to the additional capacitor and the storage capacitor is formed, and a patterning process is performed on the same, thereby, for example, one electrode of the additional capacitor and the storage capacitor. This means that the lower electrode is formed in accordance with each location and having a unique pattern shape. In other words, the additional capacity and the storage capacity are formed at the same opportunity in the manufacturing process stage. Since the additional capacity and the storage capacity are manufactured on the same occasion as described above, it is possible to realize a simplification of the manufacturing process or a reduction in manufacturing cost as compared with the case where these are manufactured separately. it can. In other words, the additional capacitor can be easily manufactured with the same configuration as that of the storage capacitor by using a process for manufacturing the storage capacitor necessary for enhancing the pixel potential holding characteristic.

  Further, particularly in the present invention, at least one of the lower electrode and the upper electrode of the storage capacitor is made of a low resistance film. Here, the “low resistance film” according to the present invention is a conductive film whose electric resistance per unit quantity such as sheet resistance is lower than that of the conductive polysilicon film. For example, the “low resistance film” is made of a conductive metal film such as an aluminum film. That is, the storage capacitor has, for example, a MIS (Metal Insulator Semiconductor) structure in which the lower electrode is formed from a polysilicon film and the upper electrode is formed from a low-resistance metal film. Alternatively, the storage capacitor has, for example, an MIM (Metal Insulator Metal) structure in which the lower electrode and the upper electrode are formed from a low-resistance metal film. Here, as described above, since the additional capacitor has the same laminated structure as the storage capacitor, at least one of the pair of electrodes constituting the additional capacitor is also made of a low resistance film such as an aluminum film. That is, the additional capacitor has, for example, a MIS structure or an MIM structure, like the storage capacitor. Therefore, the dielectric film constituting the additional capacitor can be formed from a dielectric material having a high dielectric constant (that is, a High-K material). Therefore, it is possible to make the additional capacitance so as to have a capacitance value sufficient to reduce display unevenness in a relatively small area. In other words, for example, an additional capacitor can be efficiently formed in a region on the substrate where no other wiring or circuit is formed (that is, a so-called dead space), and high density and downsizing of the device can be realized. it can.

  Furthermore, if any of the pair of electrodes constituting the additional capacitor is formed of a relatively high resistance film such as a conductive polysilicon film, a predetermined potential is supplied to the additional capacitor, for example. The fixed potential line is formed from a low-resistance film disposed in a layer different from the pair of electrodes constituting the additional capacitor, and further, a contact hole for electrically connecting the fixed potential line and the additional capacitor, It becomes necessary to form each additional capacitor, and the laminated structure on the substrate becomes complicated. However, in the present invention, in particular, at least one of the pair of electrodes constituting the additional capacitor is made of a low resistance film such as an aluminum film, for example, the fixed potential side capacitor electrode of the pair of electrodes constituting the additional capacitor, for example, It can be formed as a part of a fixed potential line for supplying a predetermined potential. Therefore, the additional capacitor can be formed without incurring a complicated laminated structure on the substrate. Accordingly, since the degree of freedom in layout when forming the additional capacitor is high, it is possible to efficiently form the additional capacitor in the dead space on the substrate.

  As described above, according to the first electro-optical device of the present invention, a high-quality image without display unevenness along the data line is displayed while realizing high density and downsizing of the device. It becomes possible.

  In one aspect of the first electro-optical device according to the invention, the lower electrode and the upper electrode are made of a metal film.

  According to this aspect, the storage capacitor and the additional capacitor have an MIM structure. Therefore, a capacitor can be formed with a simple structure. That is, for example, the fixed potential line for supplying a predetermined potential to the storage capacitor and the additional capacitor can be formed from the metal film constituting the lower electrode or the upper electrode, so that the laminated structure on the substrate is not complicated. Capacitance can be added to the data line.

  In another aspect of the first electro-optical device according to the invention, the lower electrode is made of a conductive polysilicon film, and the upper electrode is made of a metal film.

  According to this aspect, the storage capacitor and the additional capacitor have a MIS structure. For this reason, for example, an oxidation treatment for oxidizing the upper surface of one electrode constituting the additional capacitor (that is, an electrode made of the same film as the lower electrode) is performed, or a dielectric is formed on the one electrode. By performing a baking process for baking the dielectric film after the films are stacked, the breakdown voltage of the storage capacitor can be increased. Therefore, the dielectric film can be formed from a High-K material such as a silicon nitride film. Therefore, the additional capacitor can be formed in a relatively small area so as to have a capacitance value sufficient to reduce display unevenness.

  In another aspect of the first electro-optical device according to the invention, the additional capacitor is formed on a lower layer side than the data line.

  According to this aspect, the additional capacitance is formed on the lower layer side than the data line. That is, the storage capacitor having the same stacked structure as the additional capacitor is also formed on the lower layer side than the data line. Therefore, compared with the case where the additional capacitor (and the storage capacitor) is formed on the upper layer side than the data line, the storage capacitor is typically arranged on the lower layer side than the storage capacitor and the data line. And in close proximity through an interlayer insulating film. Therefore, the channel region of the thin film transistor as an example of the pixel switching element can be reliably shielded against the incident light from the upper layer side. As a result, the light leakage current in the thin film transistor is reduced during the operation of the device, and the contrast ratio can be improved.

  The additional capacitor may be formed on the upper layer side than the data line. In this case, the storage capacitor is formed on the upper layer side than the data line, but the storage capacitor is formed so as to at least partially overlap the pixel switching element when seen in plan on the substrate. The pixel switching element can be shielded against incident light from the upper layer side.

  In another aspect of the first electro-optical device according to the invention, one electrode constituting the additional capacitor has a predetermined potential.

  According to this aspect, the additional capacity can be suitably functioned. That is, it is possible to accumulate an appropriate amount of charge according to the potential difference between the voltage corresponding to the image signal supplied to the data line and the predetermined potential by the additional capacitor. The “predetermined potential” according to the present invention means a predetermined potential regardless of a change in image signal potential or image data, for example, a fixed potential that is completely fixed at a constant potential with respect to the time axis. Alternatively, it may be a fixed potential that is fixed at a constant potential for a certain period with respect to the time axis (for example, an inverted potential that is inverted with respect to a reference potential every certain period).

In the above-described aspect in which one electrode constituting the additional capacitor is set to a predetermined potential, the counter electrode is formed on the counter substrate, and is disposed on the counter substrate so as to face the substrate on which the pixel region is formed. A counter electrode provided so as to oppose to the substrate, a driving circuit for driving the data line, the scanning line, and the pixel electrode, disposed on one of the counter substrate and the substrate, and the counter electrode A first power source for supplying a predetermined potential to the electrode; and a second power source for supplying a predetermined potential to the drive circuit, wherein the one electrode is electrically connected to the first power source or the second power source. Thus, the electric potential may be set to a predetermined potential.

  In this case, a power source for setting one electrode constituting the additional capacitor to a predetermined potential and a power source for setting the counter electrode to a predetermined potential (that is, the counter electrode potential) (that is, the first power source), or Since the power supply for supplying a predetermined potential to be supplied to the drive circuit (that is, the second power supply) is shared, the device configuration can be simplified. This aspect is intended to include the case where the first power source and the second power source are one common power source.

  In the above-described aspect in which one electrode constituting the additional capacitor has a predetermined potential, the storage capacitor constant potential line for supplying a predetermined potential to either one of the lower electrode and the upper electrode is provided. The electrode may be configured to have a predetermined potential by being electrically connected to the storage capacitor fixed potential line.

  In this case, the wiring for setting one electrode constituting the additional capacitor to a predetermined potential and the storage capacitor fixed potential line for supplying the predetermined potential to the fixed potential side capacitor electrode of the storage capacitor are shared. Therefore, the device configuration can be simplified. Further, in this aspect, since the predetermined potential that is almost or completely equal is supplied to the additional capacitor and the storage capacitor, the voltage corresponding to the image signal in the storage capacitor and the voltage corresponding to the image signal in the additional capacitor are almost or completely reduced. Can match. Therefore, the voltage generated in the additional capacitor can be suppressed.

  In another aspect of the first electro-optical device according to the invention, the first electro-optical device is disposed in a peripheral region located around a pixel region in which the pixel electrode is provided, and an image signal is output to the data line according to a sampling signal. A sampling circuit including a plurality of sampling switches for supplying the sampling signal, and a data line driving circuit that is disposed in the peripheral region and sequentially supplies the sampling signal for each sampling switch corresponding to the data line, The additional capacitor is disposed in a region located between the region where the sampling circuit is disposed and the pixel region.

  According to this aspect, by arranging the additional capacitor between the region where the sampling circuit is disposed and the pixel region, the additional capacitor can be efficiently formed on the substrate having a limited area. Therefore, it is possible to realize high density and downsizing of the device.

  Furthermore, according to this aspect, the additional capacitor can be electrically connected between the drain of the thin film transistor which is an example of the sampling switch and the data line. Therefore, it is possible to suppress the push-down amount of the image signal potential written to the data line from being increased due to the influence of the parasitic capacitance between the gate and the drain of the thin film transistor. That is, by electrically connecting the additional capacitor immediately after the output side of the sampling switch, it is possible to suppress the push-down in the sampling switch from changing the potential of the data line.

  In another aspect of the first electro-optical device according to the invention, the data line driving circuit is provided on one end side of the data line, and drives the data line. It is provided on the other end side of the data line.

  According to this aspect, the arrangement relationship of various components when the data line is the center is suitable. In this aspect, since the data line driving circuit is arranged at one end of the data line and the additional capacitor is arranged at the other end, the flow of the image signal is the data line driving circuit, the data line (and the pixel switching element connected thereto, The pixel electrode) and the additional capacitor, and the transmission of the image signal to the pixel electrode without delay is realized, and the charge accumulation in the additional capacitor is performed by using the used image signal. In other words, according to this aspect, it is possible to effectively avoid a situation in which the data line is provided with an additional capacitor that can also be a kind of obstacle, but can be adversely affected.

  In this embodiment, a sampling circuit or the like may be provided between the data line driving circuit and the data line.

  In another aspect of the first electro-optical device according to the present invention, N (provided that N is supplied to each of a plurality of data line groups each including N data lines as one group among the plurality of data lines). Is a natural number greater than or equal to 2) N image signal lines for supplying serial-parallel converted image signals, and among the additional capacitors, data located at the end of the group consisting of the N data lines A capacitance value of a first additional capacitor electrically connected to the line and a second additional capacitor electrically connected to a data line different from the data line located at the end of the group among the N data lines. It is different from the capacitance value.

  According to this aspect, at the time of driving, N-system image signals subjected to serial-parallel conversion are supplied to N image signal lines, and further supplied to, for example, a sampling circuit. For example, in order to realize high-definition image display while suppressing an increase in drive frequency, serial image signals are converted into three-phase, six-phase, twelve-phase, twenty-four-phase,. It is generated by being converted into a plurality of parallel image signals. In parallel with the supply of the image signal, the sampling signal is sequentially supplied to each sampling switch corresponding to the data line group, for example, by the data line driving circuit. Then, N image signals are sequentially supplied to the plurality of data lines by the sampling circuit for each data line group according to the sampling signal. Therefore, data lines belonging to the same data line group are driven simultaneously.

  When the driving is performed for each data group in this way, the image signal is supplied to one data line group among the plurality of data line groups, and the data line belongs to the one data line group and the one data line. The potential of the data line adjacent to another data line group driven next to the group and the potential of the data line belonging to the other data line group may differ depending on the contents of the displayed image.

  When the push-down amount of the image signal potential in the two data lines located at both ends of the data line group differs from the push-down amount in the other data lines belonging to the same data line group due to such a potential difference, for example, these 2 The capacitance values of the two additional capacitors (that is, the first additional capacitors) corresponding to the respective data lines are connected to other additional capacitors (that is, electrically connected to other data lines included in the data line group). , The amount of pushdown in each data line can be made uniform. Therefore, display unevenness along the data line can be reduced or prevented.

  In order to solve the above problems, a second electro-optical device according to the present invention is provided on a substrate in correspondence with a plurality of data lines and a plurality of scanning lines intersecting with each other and the intersection of the data lines and the scanning lines. A pixel switching element provided corresponding to the pixel electrode, a predetermined potential, a fixed potential line formed from a low-resistance film, and a first electrode extended from the fixed potential line And an additional capacitor including a second electrode electrically connected to the data line.

  According to the second electro-optical device according to the present invention, during the operation, a voltage corresponding to the image signal is applied to the pixel electrode in substantially the same manner as the first electro-optical device according to the present invention described above. .

  The second electro-optical device according to the present invention includes an additional capacitor electrically connected to the data line, similarly to the above-described first electro-optical device according to the present invention. Therefore, the capacity around the data line can be appropriately secured. Therefore, it is possible to suppress the push-down of the image signal potential written to the data line. As a result, it is possible to reduce or prevent the occurrence of display unevenness along, for example, the data line due to the push-down of the image signal potential written to the data line.

  In the present invention, the first electrode constituting the additional capacitor is extended from the fixed potential line and functions as a fixed potential side electrode. On the other hand, the second electrode constituting the additional capacitor is electrically connected to the data line and functions as a pixel potential side electrode. The fixed potential line is formed of a low resistance film such as an aluminum film. That is, the first electrode extending from the fixed potential line is also formed from the low resistance film. Here, if any of the pair of electrodes constituting the additional capacitor is formed of a relatively high resistance film such as a conductive polysilicon film, a predetermined potential is supplied to the additional capacitor, for example. The fixed potential line is formed from a low-resistance film disposed in a layer different from the pair of electrodes constituting the additional capacitor, and further, a contact hole for electrically connecting the fixed potential line and the additional capacitor, It becomes necessary to form each additional capacitor, and the laminated structure on the substrate becomes complicated. However, in the present invention, in particular, the first electrode constituting the additional capacitor is extended from the fixed potential line. In other words, the first electrode constituting the additional capacitor is formed as a part of the fixed potential line that supplies a predetermined potential. Therefore, the additional capacitor can be formed without incurring a complicated laminated structure on the substrate. Accordingly, since the degree of freedom in layout when forming the additional capacitor is high, it is possible to efficiently form the additional capacitor in the dead space on the substrate.

  As described above, according to the second electro-optical device according to the present invention, a high-quality image without display unevenness along the data line is displayed while realizing high density and downsizing of the device. It becomes possible.

  In order to solve the above problems, an electronic apparatus according to the present invention includes the above-described electro-optical device according to the present invention (including various aspects thereof).

  According to the electronic apparatus of the present invention, since it includes the first or second electro-optical device according to the present invention described above, a projection display device, a television, Various electronic devices such as a cellular phone, an electronic notebook, a word processor, a viewfinder type or a monitor direct-view type video tape recorder, a workstation, a video phone, a POS terminal, and a touch panel can be realized. In addition, as an electronic apparatus of the present invention, for example, an electrophoretic device such as electronic paper, an electron emission device (Field Emission Display and Conduction Electron-Emitter Display), and a display device using these electrophoretic device and electron emission device are realized. Is also possible.

  The operation and other advantages of the present invention will become apparent from the best mode for carrying out the invention described below.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the following embodiments, a driving circuit built-in type TFT active matrix driving type liquid crystal device, which is an example of the electro-optical device of the present invention, is taken as an example.
<First Embodiment>
The liquid crystal device according to the first embodiment will be described with reference to FIGS.

  First, the overall configuration of the liquid crystal device according to the present embodiment will be described with reference to FIGS. 1 and 2. FIG. 1 is a plan view showing the overall configuration of the liquid crystal device according to this embodiment, and FIG. 2 is a cross-sectional view taken along the line HH ′ of FIG.

  1 and 2, in the liquid crystal device 100 according to the present embodiment, the TFT array substrate 10 and the counter substrate 20 are arranged to face each other. A liquid crystal layer 50 is sealed between the TFT array substrate 10 and the counter substrate 20, and the TFT array substrate 10 and the counter substrate 20 are surrounded by an image display region 10a as an example of the “pixel region” according to the present invention. They are bonded to each other by a sealing material 52 provided in a sealing region located in the area.

  In FIG. 1, a light-shielding frame light-shielding film 53 that defines the frame area of the image display region 10a is provided on the counter substrate 20 side in parallel with the inside of the seal region where the sealing material 52 is disposed. A data line driving circuit 101 and an external circuit connection terminal 102 are provided along one side of the TFT array substrate 10 in a region located outside the sealing region in which the sealing material 52 is disposed in the peripheral region. The sampling circuit 7 is provided so as to be covered with the frame light shielding film 53 on the inner side of the seal region along the one side. The scanning line driving circuit 104 is provided so as to be covered with the frame light-shielding film 53 inside the seal region along two sides adjacent to the one side. On the TFT array substrate 10, vertical conduction terminals 106 for connecting the two substrates with the vertical conduction material 107 are arranged in regions facing the four corner portions of the counter substrate 20. Thus, electrical conduction can be established between the TFT array substrate 10 and the counter substrate 20.

  On the TFT array substrate 10, a lead wiring 90 is formed for electrically connecting the external circuit connection terminal 102 to the data line driving circuit 101, the scanning line driving circuit 104, the vertical conduction terminal 106, and the like. . The lead wiring 90 includes an image signal line 171 and a counter electrode potential line 91 which will be described later.

  Although not shown here, as will be described later, a plurality of capacitors (additional capacitors) electrically connected to the respective data lines are arranged in a peripheral region located around the image display region 10a.

  In FIG. 2, on the TFT array substrate 10, a laminated structure in which wiring such as a pixel switching TFT (Thin Film Transistor) as a driving element, a scanning line, and a data line is formed. In the image display area 10a, pixel electrodes 9a are provided in a matrix on the upper layer of wiring such as pixel switching TFTs, scanning lines, and data lines. An alignment film is formed on the pixel electrode 9a. On the other hand, a light shielding film 23 is formed on the surface of the counter substrate 20 facing the TFT array substrate 10. The light shielding film 23 is formed of, for example, a light shielding metal film or the like, and is patterned, for example, in a lattice shape in the image display region 10a on the counter substrate 20. On the light shielding film 23, a counter electrode 21 made of a transparent material such as ITO is formed on almost the entire surface so as to face the plurality of pixel electrodes 9a. An alignment film is formed on the counter electrode 21. The liquid crystal layer 50 is made of, for example, a liquid crystal in which one or several types of nematic liquid crystals are mixed, and takes a predetermined alignment state between the pair of alignment films.

  Although not shown here, as will be described later, in the peripheral region on the TFT array substrate 10, an inspection circuit for inspecting the quality, defects, etc. of the liquid crystal device during the manufacturing or at the time of shipment is formed. .

  Next, the electrical configuration of the liquid crystal device according to the present embodiment will be described with reference to FIG. FIG. 3 is a block diagram showing the electrical configuration of the liquid crystal device according to this embodiment.

  In FIG. 3, the liquid crystal device 100 includes a scanning line driving circuit 104, a data line driving circuit 101, a sampling circuit 7, an inspection circuit 900, an image signal line 171, and a capacitor CA in the peripheral region of the TFT array substrate 10.

  When the Y start pulse DY is input, the scanning line driving circuit 104 sequentially generates and outputs the scanning signals Y1,..., Ym at a timing based on the Y clock signal CLY and the inverted Y clock signal CLYinv. When the X start pulse DX is input, the data line driving circuit 101 sequentially generates and outputs sampling signals S1, S2,..., Sn at a timing based on the X clock signal CLX and the inverted X clock signal XCLXinv. Each of the scanning line driving circuit 104 and the data line driving circuit 101 includes signal processing means such as a shift register including a plurality of TFTs formed in the peripheral area of the image display area 10 a on the TFT array substrate 10.

  The sampling circuit 7 includes a plurality of sampling switches 77 provided for each data line 6a. Each sampling switch 77 is composed of a P-channel or N-channel single-channel TFT. For this reason, as compared with the case where each sampling switch 77 is composed of complementary TFTs, the area on the TFT array substrate 10 required for disposing each sampling switch 77 can be reduced, so that a plurality of samplings can be obtained. The switches 77 can be arranged at a finer pitch. This makes it possible to increase the definition of the display image.

  The liquid crystal device 100 includes, in an image display region 10a occupying the center of the TFT array substrate 10, data lines 6a, scanning lines 3a, and capacitor lines 300 as "storage capacitor fixed potential lines" according to the present invention. ing. Pixel portions 700 are provided in a matrix at positions corresponding to intersections where the data lines 6a and the scanning lines 3a intersect each other. The pixel unit 700 includes a liquid crystal element 118, a pixel switching TFT 30, and a storage capacitor 70. The liquid crystal element 118 includes a pixel electrode 9a, a counter electrode 21, and a liquid crystal layer 50 sandwiched between the pair of electrodes (see FIG. 2). The capacitor line 300 is electrically connected to the counter electrode potential line 91. The counter electrode potential line 91 is electrically connected to a constant potential power source (not shown) via an external circuit connection terminal 102 (see FIG. 1). The potential of the power source supplied to the counter electrode potential line 91 (and the capacitor line 300 electrically connected thereto) is supplied to the counter electrode 21 (see FIG. 2) disposed opposite to the pixel electrode 9a. The counter electrode potential LCCOM is an example of the “predetermined potential” according to the invention. The capacitor line 300 is electrically connected to one electrode constituting the storage capacitor 70 (in this embodiment, as described later, a part of the capacitor line 300 constitutes one electrode of the storage capacitor 70. ing). The potential of the one electrode is maintained at the counter electrode potential LCCOM when the liquid crystal device 100 is driven. The storage capacitor 70 is added in parallel with the liquid crystal element 118. Since the voltage of the pixel electrode 9a is held by the storage capacitor 70 for a time that is, for example, three orders of magnitude longer than the time when the image signal is applied, the holding characteristics are improved, so that a high contrast ratio is realized.

  Each of the image signal lines 171 is electrically connected to the corresponding data line 6 a via the sampling circuit 7. Image signals of N systems (N = 6, that is, 6 systems in this embodiment) obtained by serial-parallel conversion of one system of input image data VID supplied from an external circuit are turned on / off according to the sampling signal Si. It is supplied to each of the data lines 6a via the sampling switch 77 to be switched. The N system image signals are generated, for example, by converting one system of input image data using signal conversion means such as an image signal supply circuit (not shown). Serial-parallel conversion is also called serial-parallel expansion or phase expansion.

  In this embodiment, six systems, that is, six-phase (N = 6) image signals VID1 to VID6 are generated, and six image signal lines 171 are provided corresponding to these six-phase image signals. Further, in the image signal supply circuit (not shown), the voltages of the image signals VID1 to VID6 are inverted to the positive polarity and the negative polarity with respect to the counter electrode potential LCCOM which is the reference potential, and thus the polarity-inverted image. Signals VID1 to VID6 are output. Note that the number of phase expansion of the image signal (that is, the number of image signal sequences that are serial-parallel expanded) is not limited to six phases.

  The inspection circuit 900 is electrically connected to the data line 6 a and supplies an inspection signal to each pixel unit 700.

  The capacitor CA is a plurality of capacitors Ca (i) -k (where i = 1, 2,..., N, n are natural numbers greater than or equal to 2) as an example of the “additional capacitor” according to the present invention. 1, 2, ..., N. In this embodiment, N = 6). The plurality of capacitors Ca (i) -k are electrically connected to the capacitance forming constant potential line 310 and each data line 6a. The capacitance forming constant potential line 310 is electrically connected to the counter electrode potential line 91 and supplied with the counter electrode potential LCCOM. When the sampling switch 77 is turned on by such a capacitor Ca (i) -k, the image signal potential supplied to the data line 6a becomes smaller than the original image signal potential (ie, , Pushdown) can be reduced or prevented. That is, for example, the capacitance of the capacitor Ca (i) -k is added to the wiring capacitance of the data line 6a or the capacitance generated by the overlapping of the data line 6a and another wiring, thereby reducing the capacitance around the data line 6a. It can be secured appropriately. Therefore, it is possible to suppress the fluctuation in the potential that the data line 6a should hold, that is, the push-down of the image signal potential written to the data line 6a. As a result, it is possible to reduce or prevent the occurrence of display unevenness along, for example, the data line 6a due to the push-down of the image signal potential written to the data line 6a.

  In the present embodiment, as will be described later, the plurality of data lines 6a are sequentially driven for each data line group including six data lines 6a as one group. The capacitor Ca (i) -k includes six data lines 6a belonging to the (i) th data line group (that is, a data line group including six data lines 6a to which the sampling signal Si is simultaneously supplied). It is connected to the (k) th data line 6a from the left.

  Next, the operation principle of the liquid crystal device according to the present embodiment will be described with reference to FIG. Note that the liquid crystal device 100 according to the present embodiment is driven by a 1H inversion driving method which is an example of a line inversion method.

  In FIG. 3, a TFT 30 is an example of the “pixel switching element” according to the present invention, and is provided to apply an image signal supplied from the data line 6a to a selected pixel. The gate of the TFT 30 is electrically connected to the scanning line 3a, and the source is electrically connected to the data line 6a. The drain of the TFT 30 is electrically connected to the pixel electrode 9a (see FIG. 2) constituting the liquid crystal element 118. The pixel electrode 9a holds a liquid crystal capacitance formed between the pixel electrode 9a and a counter electrode 21 described later for a certain period according to an image signal. One electrode of the storage capacitor 70 is electrically connected to the drain of the TFT 30 in parallel with the pixel electrode 9a, and the other electrode is connected to the capacitor line 300 supplied with the counter electrode potential LCCOM and maintained at a constant potential. Is done.

  The liquid crystal device 100 employs, for example, a TFT active matrix driving method, applies scanning signals Y1, Y2,. An image signal is applied from the data line driving circuit 101 to the data line 6a in the column of the selected pixel region. At this time, the image signal may be supplied to each data line 6a line by line. As a result, the image signal is supplied to the pixel electrode 9a in the selected pixel region. In the liquid crystal device 100, since the TFT array substrate 10 and the counter substrate 20 are disposed to face each other via the liquid crystal layer 50 (see FIG. 2), an electric field is applied to the liquid crystal layer 50 for each of the pixels arranged in a partition as described above. Is applied, the amount of transmitted light between the two substrates is controlled for each pixel, and the image is displayed in gradation. At this time, the image signal held in each pixel unit 700 is prevented from leaking by the storage capacitor 70.

  Image signals VID <b> 1 to VID <b> 6 that are serially and parallelly developed in six phases are supplied to each pixel unit 700 via N image signals 171 in this embodiment. As will be described below, the data lines 6a are sequentially driven for each data line group including six data lines 6a corresponding to the number of image signal lines 171 as a group.

  A sampling signal Si (i = 1, 2,..., N) is sequentially supplied from the data line driving circuit 101 to each sampling switch 77 corresponding to the data line group, and each sampling switch 77 is turned on according to the sampling signal Si. It becomes.

  Therefore, the image signals VID1 to VID6 are simultaneously supplied from the six image signal lines 171 simultaneously to the data lines 6a belonging to the data line group and sequentially for each data line group via the sampling switch 77 switched to the ON state. Thus, the data lines 6a belonging to one data line group are driven simultaneously. Therefore, according to the liquid crystal device 100, since the data line 6a is driven for each data line group, the driving frequency can be suppressed.

  An applied voltage defined by the potentials of the pixel electrode 9 a and the counter electrode 21 is applied to the liquid crystal element 118. The liquid crystal modulates light and enables gradation display by changing the orientation and order of the molecular assembly depending on the applied voltage level. In the normally white mode, the transmittance for incident light is reduced according to the voltage applied in units of each pixel, and in the normally black mode, the light is incident according to the voltage applied in units of each pixel. The light transmittance is increased, and light having a contrast corresponding to the image signals VID1 to VID6 is emitted from the liquid crystal device 100 as a whole, and an image is displayed.

  In this embodiment, since the 1H inversion driving method is adopted, the direction along the data line 6a (that is, in FIG. 3) during the image display period of the mth field (where m is a natural number) or frame. A voltage having a polarity different from that of the adjacent row is applied to each row of the pixel electrodes 9a arranged in parallel in the Y direction), and the pixel unit 700 is in a state where a liquid crystal driving voltage having a reverse polarity is applied to each row. Driven. More specifically, the polarity of the liquid crystal drive voltage is inverted in the image display period of the (m + 1) th field or frame following the mth field. After the (m + 2) th field or frame, the same state as the mth and (m + 1) th is repeated periodically. When the polarity of the voltage applied to the liquid crystal layer 50 is periodically reversed in this way, application of a DC voltage to the liquid crystal is prevented, and deterioration of the liquid crystal is suppressed. In addition, since the polarity of the applied voltage is reversed for each row of the pixel electrodes 9a, crosstalk and flicker are reduced. The potential of the electrode electrically connected to the capacitor line 300 among the pair of electrodes constituting the storage capacitor 70 is constant because it is maintained at the counter electrode potential LCCOM, but is electrically connected to the capacitor line 300. The potential of the non-existing electrode periodically becomes a potential having a reverse polarity due to the applied voltage to the counter electrode potential LCCOM, that is, the polarity of the image signal potential.

  In this embodiment, 1H inversion driving is exemplified as a driving method of the liquid crystal device 100, but the driving method is a 1S inversion driving method in which a voltage having a reverse polarity is applied to each pixel column, or a reverse polarity for each adjacent pixel. A dot inversion driving method in which the above voltage is applied may be employed.

  Next, a specific configuration of the pixel portion that realizes the above-described operation will be described with reference to FIGS. FIG. 4 is a plan view of a plurality of pixel unit groups adjacent to each other on the TFT array substrate on which the data lines, scanning lines, pixel electrodes, etc. are formed in the liquid crystal device according to this embodiment. It is sectional drawing in the AA 'line of 4. FIG.

  In FIG. 4, a plurality of pixel electrodes 9a are provided in a matrix on the TFT array substrate 10 (the outline is indicated by a dotted line portion 9a '), and data along the vertical and horizontal boundaries of the pixel electrode 9a is provided. Line 6a and scanning line 3a are provided. The data line 6a is made of, for example, a metal film such as an aluminum film or an alloy film, and the scanning line 3a is made of, for example, a conductive polysilicon film. The scanning line 3a is arranged so as to face the channel region 1a 'indicated by the hatched region rising to the right in the drawing in the semiconductor layer 1a, and the scanning line 3a functions as a gate electrode. In other words, each of the intersections of the scanning line 3a and the data line 6a is provided with a pixel switching TFT 30 in which the main line portion of the scanning line 3a is opposed to the channel region 1a ′ as a gate electrode.

  As shown in FIG. 5, the liquid crystal device 100 includes a transparent TFT array substrate 10 and a transparent counter substrate 20 disposed to face the TFT array substrate 10. The TFT array substrate 10 is made of, for example, a quartz substrate, a glass substrate, or a silicon substrate, and the counter substrate 20 is made of, for example, a glass substrate or a quartz substrate. A pixel electrode 9a is provided on the TFT array substrate 10, and an alignment film 16 that has been subjected to a predetermined alignment process such as a rubbing process is provided above the pixel electrode 9a. Among these, the pixel electrode 9a is made of a transparent conductive film such as an ITO film. On the other hand, the counter substrate 20 is provided with a counter electrode 21 over almost the entire surface thereof, and an alignment film 22 subjected to a predetermined alignment process such as a rubbing process is provided below the counter electrode 21. Of these, the counter electrode 21 is made of a transparent conductive film such as an ITO film, for example, and the alignment films 16 and 22 are made of a transparent organic film such as a polyimide film, for example, in the same manner as the pixel electrode 9a described above. The liquid crystal layer 50 takes a predetermined alignment state by the alignment films 16 and 22 in a state where an electric field from the pixel electrode 9a is not applied.

  As shown in FIG. 5, the TFT 30 has an LDD (Lightly Doped Drain) structure, and as its constituent elements, the scanning line 3a functioning as a gate electrode as described above, for example, a scanning line made of a polysilicon film. The channel region 1a ′ of the semiconductor layer 1a in which a channel is formed by the electric field from 3a, the insulating film 2 including the gate insulating film that insulates the scanning line 3a from the semiconductor layer 1a, the low-concentration source region 1b in the semiconductor layer 1a, and the low A concentration drain region 1c, a high concentration source region 1d, and a high concentration drain region 1e are provided.

  The TFT 30 preferably has an LDD structure as shown in FIG. 5, but may have an offset structure in which impurities are not implanted into the low concentration source region 1b and the low concentration drain region 1c, or a part of the scanning line 3a. A self-aligned TFT may be used in which a high concentration source region and a high concentration drain region are formed in a self-aligned manner by implanting impurities at a high concentration using a gate electrode made of In the present embodiment, the gate electrode of the pixel switching TFT 30 has a single gate structure in which only one gate electrode is disposed between the high-concentration source region 1d and the high-concentration drain region 1e. A gate electrode may be disposed. If the TFT is configured with dual gates or triple gates or more in this way, leakage current at the junction between the channel and the source and drain regions can be prevented, and the current during OFF can be reduced. Further, the semiconductor layer 1a constituting the TFT 30 may be a non-single crystal layer or a single crystal layer. A known method such as a bonding method can be used for forming the single crystal layer. By making the semiconductor layer 1a a single crystal layer, it is possible to improve the performance of peripheral circuits in particular.

  In FIG. 5, the storage capacitor 70 is provided on the upper layer side of the TFT 30 through the interlayer insulating film 41, and the lower electrode 71 connected to the high concentration drain region 1 e of the TFT 30 and the pixel electrode 9 a, and the capacitor line 300. The upper electrode 300a made of a part of the upper electrode 300a is formed so as to be opposed to each other with the dielectric film 75 interposed therebetween.

  The lower electrode 71 is made of a conductive polysilicon film, and is electrically connected to the high-concentration drain region 1 e of the TFT 30 through a contact hole 83 opened in the interlayer insulating film 41. That is, the lower electrode 71 functions as a pixel potential side capacitance electrode that is set to the pixel potential. The extending portion of the lower electrode 71 is electrically connected to the pixel electrode 9a through a contact hole 85 that is opened through the interlayer insulating film 43 and the interlayer insulating film. That is, the lower electrode 71 has a function of electrically connecting the pixel electrode 9a and the high-concentration drain region 1e of the TFT 30 via the contact holes 83 and 85 in addition to the function as a pixel potential side capacitor electrode. . An HTO (High Temperature Oxide) film is formed on the upper layer side of the lower electrode 71 as will be described later.

  The interlayer insulating films 41, 42, and 43 are each formed of, for example, NSG (non-silicate glass). In addition, silicate glass such as PSG (phosphorus silicate glass), BSG (boron silicate glass), BPSG (boron phosphorous silicate glass), silicon nitride, silicon oxide, or the like is used for the interlayer insulating films 41, 42, and 43, respectively. it can.

  The dielectric film 75 is made of a relatively thin silicon nitride (SiN) film having a thickness of about 5 to 300 nm, for example. From the viewpoint of increasing the storage capacitor 70, the thinner the dielectric film 75 is, the better as long as the reliability of the film is sufficiently obtained. The dielectric film 75 may be subjected to a firing process. In this case, the density of the dielectric film can be increased.

  The upper electrode 300a is formed as a part of the capacitor line 300 formed of an aluminum film, and functions as a fixed potential side capacitor electrode disposed to face the lower electrode 71. The capacitor line 300 and the upper electrode 3a are not limited to the aluminum film, and may be formed of another conductive film whose electric resistance per unit quantity such as sheet resistance is lower than that of the conductive polysilicon film. . The capacitor line 300 and the upper electrode 3a may be a two-layer film or a multilayer film having a stacked structure in which a plurality of conductive films are stacked. When viewed in a plan view, the capacitor line 300 is formed so as to overlap the region where the scanning line 3a is formed, as shown in FIG. More specifically, the capacitor line 300 includes a main line portion that extends along the scanning line 3a, a protruding portion that protrudes upward along the data line 6a from each location that intersects the data line 6a, and a contact hole. A portion corresponding to 85 is provided with a constricted portion slightly constricted. Of these, the protruding portion contributes to an increase in the formation region of the storage capacitor 70 using the region above the scanning line 3a and the region below the data line 6a. Further, as described above, the capacitor line 300 is electrically connected to the constant potential source via the counter electrode potential line 91 wired around the image display region 10a, and thus has a predetermined potential (that is, the counter electrode potential LCCOM). ).

  Particularly in the present embodiment, the lower electrode 71 is made of a conductive polysilicon film, and the upper electrode 300a is made of an aluminum film. That is, the storage capacitor 70 has a MIS structure in which a semiconductor film, an insulator film, and a metal film are sequentially stacked. An HTO film is formed on the upper layer side of the lower electrode 71. The HTO film is made of a high temperature silicon oxide film formed by an oxidation process for oxidizing the upper surface of the lower electrode 71 made of a polysilicon film, or a film formed by LP (Low Pressure) -CVD. Thus, the withstand voltage of the storage capacitor 70 is increased by the HTO film formed between the lower electrode 71 and the dielectric film 75. Therefore, the generation of leakage current can be suppressed or prevented, and the capacity of the storage capacitor 70 can be increased by using a high dielectric constant material (that is, a high-k material). As a result, flicker, pixel unevenness, and the like are reduced or preferably eliminated, and high-quality display is possible.

  Next, the configuration of the capacitor electrically connected to the data line of the liquid crystal device according to the present embodiment will be described with reference to FIGS. 6 and 7 in addition to FIG. FIG. 6 is a plan view of the capacitor electrically connected to the data line, and FIG. 7 is a cross-sectional view taken along the line BB ′ of FIG. In FIG. 7, the scale of each layer / member is different for each layer / member so that each layer / member can be recognized on the drawing.

  In FIG. 6, the capacitors Ca (i) -k (where k = 1,..., 6) electrically connected to the data line 6a of the (i) th data line group described above with reference to FIG. A specific configuration is shown.

  In FIG. 6, capacitors Ca (i) -k (where k = 1,..., 6) are arranged on the TFT array substrate 10 in the peripheral region of the image display region 10a and the region where the sampling circuit 7 is arranged. In an area located between the display area 10a and the display area 10a, the data lines 6a are arranged along a direction (that is, a direction in which the scanning line 3a extends or an X direction).

  As shown in FIG. 7, the capacitor Ca (i) -1 extends in the direction intersecting the pixel potential side electrode 511-1 electrically connected to the data line 6a and the data line 6a, and is maintained at a predetermined potential. And a fixed potential side electrode 310a formed as a part of the capacitance forming constant potential line 310, and a dielectric film 75 is sandwiched between the pair of electrodes. The capacitors Ca (i) -2 to Ca (i) -6 are configured in substantially the same manner as the capacitor Ca (i) -1.

  In FIG. 7, the pixel potential side electrode 511-1 is formed on the interlayer insulating film 41. That is, the pixel potential side electrode 511-1 is formed of the same film (that is, a conductive polysilicon film) as the lower electrode 71 constituting the storage capacitor 70 described above with reference to FIG. The pixel potential side electrode 511-1 is electrically connected to the data line 6a through a contact hole 581 that is opened through the interlayer insulating film 42 and the dielectric film 75. Thereby, the pixel potential side electrode 511-1 has the same potential as the data line 6a. The contact hole 581 is provided inside an opening 591 provided in the fixed potential side electrode 310a. Therefore, the pixel potential side electrode 511-1 and the data line 6a are connected by the contact hole 581 while maintaining electrical insulation between the pixel potential side electrode 511-1 and the data line 6a and the fixed potential side electrode 310a. It can be electrically connected to each other.

  The fixed potential side electrode 310a (in other words, the capacitance forming constant potential line 310) is opposed to the pixel potential side electrode 511-1 on the dielectric film 75 formed on the pixel potential side electrode 511-1. Is formed. That is, the fixed potential side electrode 310a is formed of the same film (that is, an aluminum film) as the upper electrode 300a (in other words, the capacitor line 300) constituting the storage capacitor 70 described above with reference to FIG. The fixed potential side electrode 310a is formed as a part of the capacitance forming constant potential line 310 electrically connected to the counter electrode potential line 91 (see FIG. 3) for supplying the counter electrode potential LCCOM to the counter electrode 21. ing. For this reason, the potential of the fixed potential side electrode 310a is maintained at the counter electrode potential LCCOM.

  Thus, in this embodiment, in particular, the capacitor Ca (i) -k has the same stacked structure as the storage capacitor 70 (see FIG. 5). That is, the capacitor Ca (i) -k is fixed to the pixel potential side electrode 511-1 formed of the same film as the lower electrode 71 of the storage capacitor 70 and the same film as the upper electrode 300a of the storage capacitor 70. It is composed of a potential side electrode 310a and a dielectric film 75 sandwiched between the pair of electrodes. In other words, the capacitor Ca (i) -k and the storage capacitor 70 are formed at the same opportunity in the manufacturing process stage. Therefore, since the capacitor Ca (i) -k and the storage capacitor 70 are manufactured on the same occasion as described above, the manufacturing process can be simplified or the manufacturing cost can be reduced as compared with the case where each of them is manufactured separately. Cost reduction etc. can be realized. In other words, the capacitor Ca (i) -k can be easily manufactured with the same stacked structure as the storage capacitor 70 by using the process of manufacturing the storage capacitor 70 necessary for enhancing the pixel potential holding characteristic. .

  Further, in the present embodiment, in particular, the capacitor Ca (i) -k has a MIS structure that is the same laminated structure as the storage capacitor 70. Therefore, the dielectric film 75 constituting the capacitor Ca (i) -k can be formed from a dielectric material having a high dielectric constant (that is, a High-K material). Therefore, the capacitor Ca (i) -k can be formed in a relatively small area so as to have a capacitance value sufficient to reduce the display unevenness as described above. In other words, the capacitor Ca (i) -k can be efficiently formed in, for example, a dead space on the TFT array substrate 10 where other wirings and circuits are not formed, thereby realizing higher density and smaller size of the device. be able to.

  The storage capacitor 70 and the capacitor Ca (i) -k may have an MIM structure. That is, any of the pair of electrodes constituting each of the storage capacitor 70 and the capacitor Ca (i) -k may be formed of a metal film such as an aluminum film. In this case, wiring for supplying a predetermined potential to the storage capacitor 70 and the capacitor Ca (i) -k is formed from a metal film constituting the storage capacitor 70 (in other words, the capacitor Ca (i) -k). Therefore, it is possible to add capacitance to the data line 6a without complicating the laminated structure on the TFT array substrate 10.

  In addition, as shown in FIG. 7, in the present embodiment, the capacitor Ca (i) -k is formed on the lower layer side than the data line 6a. That is, in FIG. 5, the storage capacitor 70 having the same laminated structure as the capacitor Ca (i) -k is also formed on the lower layer side than the data line 6a. Therefore, as compared with the case where the capacitors Ca (i) -k (and the storage capacitor 70) are formed on the upper layer side than the data line 6a, the storage capacitor 70 is interposed between the pixel switching TFT 30 and the interlayer insulating film 41. Can be placed close together. Therefore, the channel region 1a ′ of the pixel switching TFT 30 can be reliably shielded against incident light from the upper layer side. As a result, the light leakage current in the TFT 30 is reduced during the operation of the device, and the contrast ratio can be improved.

  The capacitor Ca (i) -k may be formed on the upper layer side than the data line 6a. In this case, the storage capacitor 70 is formed on the upper layer side than the data line 6a. However, the storage capacitor 70 is formed so as to at least partially overlap the TFT 30 when viewed in plan on the TFT array substrate 10. By doing so, the TFT 30 can be shielded correspondingly to the incident light from the upper layer side.

  3 and 7, in the present embodiment, in particular, the capacitor Ca (i) -k is disposed between the region where the sampling circuit 7 is disposed and the image display region 10a. Therefore, it can be efficiently formed on the TFT array substrate 10 having a limited area. Therefore, it is possible to realize higher density and smaller size of the apparatus.

  Further, particularly in the present embodiment, immediately after the drain of the sampling switch 77 composed of a single channel TFT (in other words, the drain or output side of the sampling switch 77 rather than the portion formed in the image display region 10a in the data line 6a). ) Is electrically connected to the capacitor Ca (i) -k. Therefore, it is possible to suppress the push-down amount of the image signal potential written to the data line 6a from being increased due to the influence of the parasitic capacitance between the gate and the drain of the sampling switch 77. In other words, it is possible to suppress the push-down in the sampling switch 77 from changing the potential of the data line 6a.

  In addition, as shown in FIG. 6, in the present embodiment, in particular, the pixel potential side electrodes 511-1 and 511-6 included in each of the capacitors Ca (i) -1 and Ca (i) -6 are connected to other pixels. It is formed to have a smaller area than the potential side electrodes 511-2 to 511-5. The area where the pixel potential side electrodes 511-1 and 511-6 overlap with the fixed potential side electrode 310a and the dielectric film 75 is smaller than the other capacitors Ca (i) -2 to Ca (i) -5. Accordingly, the capacitances of the capacitors Ca (i) -1 and Ca (i) -6 are relatively smaller than the capacitances of the other capacitors Ca (i) -2 to Ca (i) -5. Is set. As a result, the image signal potentials at the two data lines 6a located at both ends of the data line group (that is, the two data lines 6a connected to the capacitors Ca (i) -1 and Ca (i) -6, respectively). Is different from the push-down amount in other data lines belonging to the same data line group (that is, four data lines 6a respectively connected to the capacitors Ca (i) -2 to Ca (i) -5). Can be suppressed. In other words, by making the capacitance values of the capacitors Ca (i) -1 and Ca (i) -6 different from the capacitance values of the capacitors Ca (i) -2 and Ca (i) -5, each data line 6a. The amount of push-down can be made uniform. Therefore, display unevenness along the data line 6a can be reduced or prevented. Even if the capacitors Ca (i) -2 and Ca (i) -5 are provided without the capacitors Ca (i) -1 and Ca (i) -6, the capacitance value of the capacitor can be optimized. Good. Also in this case, the pushdown amount in each data line 6a can be made uniform.

As described above, according to the liquid crystal device 100 according to the present embodiment, it is possible to display a high-quality image without display unevenness along the data line 6a while realizing higher density and smaller size of the device. Is possible.
<Modification>
Next, modified examples of the liquid crystal device according to the present embodiment will be described with reference to FIGS. FIG. 8 is a sectional view having the same concept as in FIG. 7 in the first modification. FIG. 9 is a sectional view having the same concept as in FIG. 7 in the second modification. FIG. 10 is a sectional view having the same concept as in FIG. 7 in the third modification.

  As shown in FIG. 8 as a first modification, the capacitor Ca (i) -1 has a fixed potential side electrode 310a, a dielectric film 75, and a pixel potential side electrode 511-1 stacked in this order from the lower layer side. It may be. According to this modification, when the contact hole 582 for connecting the data line 6a and the pixel potential side electrode 511-1 is formed, it is not necessary to avoid the fixed potential side electrode 310 (ie, for example, FIG. 7), the capacitor Ca (i) -1 can be efficiently formed on the TFT array substrate 10 having a limited area. According to this modification, the same effect as that of the above-described embodiment can be obtained. In this modification, the pixel potential side electrode 511-1 and the data line 6a are electrically connected to each other through a contact hole 582 opened in the interlayer insulating film.

  As shown in FIG. 9 as a second modification, the capacitor Ca (i) -1 is formed on the upper layer side through the interlayer insulating film 42 with respect to the data line 6a, and is connected to the pixel potential side electrode 511-1 and the dielectric. The body film 75 and the fixed potential side electrode 310a may be laminated in this order from the lower layer side. The pixel potential side electrode 511-1 is electrically connected to the data line 6a through a contact hole 584 opened in the interlayer insulating film. According to this modification, the same effect as that of the above-described embodiment can be obtained.

As shown in FIG. 10 as a third modification, the capacitor Ca (i) -1 has a fixed potential side electrode 310a, a dielectric film 75, and a pixel potential on the upper layer side of the data line 6a via the interlayer insulating film 42. The side electrode 511-1 may be laminated from the lower layer side in this order. The pixel potential side electrode 511-1 is electrically connected to the data line 6a through a contact hole 585 opened in the interlayer insulating film. The contact hole 585 is formed in a region that does not overlap the fixed potential side electrode 310a when viewed in plan on the TFT array substrate 10. According to this modification, the same effect as that of the above-described embodiment can be obtained.
Second Embodiment
Next, a liquid crystal device according to a second embodiment will be described with reference to FIG. FIG. 11 is a block diagram having the same concept as in FIG. 3 in the second embodiment. In FIG. 11, the same reference numerals are given to the same components as those according to the first embodiment shown in FIG. 3, and description thereof will be omitted as appropriate.

  As shown in FIG. 11, the liquid crystal device 120 according to the second embodiment includes the capacitor unit CB on the opposite side of the data line driving circuit 101 with respect to the image display region 10a, and thus the first embodiment described above. Unlike the liquid crystal device 100 according to the first embodiment, the other configuration is substantially the same as the liquid crystal device 100 according to the first embodiment described above.

In FIG. 11, in the present embodiment, in particular, the capacitor portion CB is provided on the opposite side of the data line driving circuit 101 with respect to the image display region 10a. The capacitor CB has a plurality of capacitors Cb (i) -k (where i = 1, 2,..., N, n are natural numbers of 2 or more, k = 1, 2,..., 6). Yes. The capacitor Cb (i) -k is connected to the other end of the data line 6a different from the one end to which the data line driving circuit 101 is connected. That is, the data line driving circuit 101 is disposed at one end of the data line 6a, and the capacitor Cb (i) -k is disposed at the other end. The capacitor Cb (i) -k has the same laminated structure as the storage capacitor 70. Therefore, the flow of the image signal is the data line driving circuit 101, the data line 6a (and the TFT 30 and the pixel electrode 9a connected to the data line 6a), and the capacitor Cb (i) -k. In addition to realizing transmission, charge accumulation in the capacitor Cb (i) -k is performed by using a used image signal. In other words, according to the liquid crystal device 120, even if the data line 6a is provided with the capacitor Cb (i) -k that can also be a kind of an obstacle, it effectively avoids a situation in which an adverse effect that may occur due to the capacitor Cb (i) -k is provided. can do.
<Electronic equipment>
Next, the case where the above-described liquid crystal device, which is an electro-optical device, is applied to various electronic devices will be described with reference to FIGS. FIG. 12 is a plan view showing a configuration example of the projector. Here, a projector using a liquid crystal device as a light valve will be described.

  As shown in FIG. 12, a projector 1100 has a lamp unit 1102 made of a white light source such as a halogen lamp. The projection light emitted from the lamp unit 1102 is separated into three primary colors of RGB by four mirrors 1106 and two dichroic mirrors 1108 arranged in the light guide 1104, and serves as a light valve corresponding to each primary color. The light enters the liquid crystal panels 1110R, 1110B, and 1110G.

  The configurations of the liquid crystal panels 1110R, 1110B, and 1110G are the same as those of the liquid crystal device described above, and are driven by R, G, and B primary color signals supplied from the image signal processing circuit. The light modulated by these liquid crystal panels enters the dichroic prism 1112 from three directions. In the dichroic prism 1112, R and B light is refracted at 90 degrees, while G light travels straight. Therefore, as a result of the synthesis of the images of the respective colors, a color image is projected onto the screen or the like via the projection lens 1114.

  Here, paying attention to the display images by the liquid crystal panels 1110R, 1110B, and 1110G, the display image by the liquid crystal panel 1110G needs to be horizontally reversed with respect to the display images by the liquid crystal panels 1110R and 1110B.

  In addition, since light corresponding to each primary color of R, G, and B is incident on the liquid crystal panels 1110R, 1110B, and 1110G by the dichroic mirror 1108, it is not necessary to provide a color filter.

  In addition to the electronic device described with reference to FIG. 12, a mobile personal computer, a mobile phone, a liquid crystal television, a viewfinder type, a monitor direct view type video tape recorder, a car navigation device, a pager, and an electronic notebook , Calculators, word processors, workstations, videophones, POS terminals, devices with touch panels, and the like. Needless to say, the present invention can be applied to these various electronic devices.

  In addition to the liquid crystal device described in the above embodiment, the present invention also includes a reflective liquid crystal device (LCOS) in which elements are formed on a silicon substrate, a plasma display (PDP), a field emission display (FED, SED), The present invention can also be applied to an organic EL display, a digital micromirror device (DMD), an electrophoresis apparatus, and the like.

  The present invention is not limited to the above-described embodiment, and can be appropriately changed without departing from the spirit or idea of the invention that can be read from the claims and the entire specification, and an electro-optical device with such a change, In addition, an electronic apparatus including the electro-optical device is also included in the technical scope of the present invention.

It is a top view which shows the whole structure of the liquid crystal device which concerns on 1st Embodiment. It is the HH 'sectional view taken on the line of FIG. 1 is a block diagram illustrating an electrical configuration of a liquid crystal device according to a first embodiment. It is a top view of a plurality of pixel part groups in a liquid crystal device concerning this embodiment. It is sectional drawing in the AA 'line of FIG. It is a top view of the capacitor electrically connected to the data line. FIG. 7 is a sectional view taken along line BB ′ in FIG. 6. It is sectional drawing with the same meaning as FIG. 7 in a 1st modification. It is sectional drawing with the same meaning as FIG. 7 in a 2nd modification. It is sectional drawing of the same meaning as FIG. 7 in a 3rd modification. It is a block diagram with the same meaning as FIG. 3 in 2nd Embodiment. It is a top view which shows the structure of the projector which is an example of the electronic device to which the electro-optical apparatus is applied.

Explanation of symbols

  3a ... Scanning line, 6a ... Data line, 7 ... Sampling circuit, 9a ... Pixel electrode, 10 ... TFT array substrate, 10a ... Image display area, 20 ... Counter substrate, 21 ... Counter electrode, 23 ... Light shielding film, 30 ... TFT , 50 ... Liquid crystal layer, 52 ... Sealing material, 53 ... Frame light shielding film, 71 ... Lower electrode, 75 ... Dielectric film, 91 ... Counter electrode potential line, 101 ... Data line driving circuit, 102 ... External circuit connection terminal, DESCRIPTION OF SYMBOLS 104 ... Scanning line drive circuit, 106 ... Vertical conduction terminal, 107 ... Vertical conduction material, 118 ... Liquid crystal element, 171 ... Image signal line, 300 ... Capacitance line, 300a ... Upper electrode, 310 ... Constant potential line for capacitance formation, 310a ... fixed potential side electrode, 581, 582, 584, 585 ... contact hole, 591 ... opening, 700 ... pixel part, 900 ... inspection circuit, CA, CB ... capacitance part, Ca (i) -k, Cb (i -k ... capacitor, the pixel-potential-side electrode 511-k

Claims (10)

In the pixel area ,
A plurality of data lines and a plurality of scanning lines intersecting each other;
And pixel electrodes provided corresponding to intersections of the data lines and the scanning lines,
A lower electrode; an upper electrode provided in a layer different from the lower electrode; and a dielectric film provided between the lower electrode and the upper electrode. A storage capacity,
Outside the pixel area,
Which has the storage capacity and the same laminate structure, and electrically connected to the additional capacitance in the data lines,
N systems of serial-parallel converted image signals are supplied to a plurality of data line groups each including N data lines (where N is a natural number of 3 or more) among the plurality of data lines. N image signal lines and
With
Among the additional capacitors, the capacitance value of the first additional capacitor electrically connected to the data line located at the end of the group consisting of the N data lines, and the group of the N data lines. An electro-optical device, wherein a capacitance value of a second additional capacitor electrically connected to a data line different from the data line located at the end is different from each other .   The electro-optical device according to claim 1, wherein the lower electrode and the upper electrode are made of a metal film. The lower electrode is made of a conductive polysilicon film,
The electro-optical device according to claim 1, wherein the upper electrode is made of a metal film.   The electro-optical device according to claim 1, wherein the additional capacitor is formed on a lower layer side than the data line.   5. The electro-optical device according to claim 1, wherein one electrode constituting the additional capacitor is set to a predetermined potential. 6. A counter substrate disposed opposite to the substrate on which the pixel region is formed ;
A counter electrode formed on the counter substrate and provided to face the pixel electrode;
A driving circuit disposed on one of the counter substrate and the substrate, for driving the data line, the scanning line, and the pixel electrode;
A first power source for supplying a predetermined potential to the counter electrode;
A second power supply for supplying a predetermined potential to the drive circuit,
The electro-optical device according to claim 5, wherein the one electrode is set to a predetermined potential by being electrically connected to the first power source or the second power source. A storage capacitor fixed potential line for supplying a predetermined potential to either one of the lower electrode and the upper electrode;
The electro-optical device according to claim 5, wherein the one electrode is set to a predetermined potential by being electrically connected to the storage capacitor fixed potential line. A sampling circuit that is disposed in a peripheral region located around a pixel region in which the pixel electrode is provided, and includes a plurality of sampling switches that respectively supply image signals to the data lines in accordance with a sampling signal;
A data line driving circuit that is arranged in the peripheral region and sequentially supplies the sampling signal for each sampling switch corresponding to the data line;
The electro-optical device according to claim 1, wherein the additional capacitor is disposed in a region located between the region where the sampling circuit is disposed and the pixel region. Provided on one end side of the data line, and comprises a data line driving circuit for driving the data line;
The electro-optical device according to claim 1, wherein the additional capacitor is provided on the other end side of the data line. An electronic device characterized by being provided with the electro-optical device according to any one of claims 1 to 9.

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